From e8fa469595e29b2dbe6dde3a77ee2ea2d9e93283 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Mon, 19 Jan 2015 12:59:42 +0000 Subject: [PATCH 2/2] xen/arm: vgic-v2: message in the emulation code should be rate-limited printk is not rated-limited by default. Therefore a malicious guest may be able to flood the Xen console. If we use gdprintk, unecessary information will be printed such as the filename and the line. Instead use XENLOG_G_ERR combine with %pv. Signed-off-by: Julien Grall --- xen/arch/arm/vgic-v2.c | 40 +++++++++++++++++++++++----------------- 1 file changed, 23 insertions(+), 17 deletions(-) diff --git a/xen/arch/arm/vgic-v2.c b/xen/arch/arm/vgic-v2.c index 9dc9a20..3b87f54 100644 --- a/xen/arch/arm/vgic-v2.c +++ b/xen/arch/arm/vgic-v2.c @@ -198,7 +198,7 @@ static int vgic_v2_distr_mmio_read(struct vcpu *v, mmio_info_t *info) case GICD_ICPIDR2: if ( dabt.size != DABT_WORD ) goto bad_width; - printk("vGICD: unhandled read from ICPIDR2\n"); + printk(XENLOG_G_ERR "%pv: vGICD: unhandled read from ICPIDR2\n", v); return 0; /* Implementation defined -- read as zero */ @@ -215,14 +215,14 @@ static int vgic_v2_distr_mmio_read(struct vcpu *v, mmio_info_t *info) goto read_as_zero; default: - printk("vGICD: unhandled read r%d offset %#08x\n", - dabt.reg, gicd_reg); + printk(XENLOG_G_ERR "%pv: vGICD: unhandled read r%d offset %#08x\n", + v, dabt.reg, gicd_reg); return 0; } bad_width: - printk("vGICD: bad read width %d r%d offset %#08x\n", - dabt.size, dabt.reg, gicd_reg); + printk(XENLOG_G_ERR "%pv: vGICD: bad read width %d r%d offset %#08x\n", + v, dabt.size, dabt.reg, gicd_reg); domain_crash_synchronous(); return 0; @@ -331,14 +331,16 @@ static int vgic_v2_distr_mmio_write(struct vcpu *v, mmio_info_t *info) case GICD_ISPENDR ... GICD_ISPENDRN: if ( dabt.size != DABT_BYTE && dabt.size != DABT_WORD ) goto bad_width; - printk("vGICD: unhandled %s write %#"PRIregister" to ISPENDR%d\n", - dabt.size ? "word" : "byte", *r, gicd_reg - GICD_ISPENDR); + printk(XENLOG_G_ERR + "%pv: vGICD: unhandled %s write %#"PRIregister" to ISPENDR%d\n", + v, dabt.size ? "word" : "byte", *r, gicd_reg - GICD_ISPENDR); return 0; case GICD_ICPENDR ... GICD_ICPENDRN: if ( dabt.size != DABT_BYTE && dabt.size != DABT_WORD ) goto bad_width; - printk("vGICD: unhandled %s write %#"PRIregister" to ICPENDR%d\n", - dabt.size ? "word" : "byte", *r, gicd_reg - GICD_ICPENDR); + printk(XENLOG_G_ERR + "%pv: vGICD: unhandled %s write %#"PRIregister" to ICPENDR%d\n", + v, dabt.size ? "word" : "byte", *r, gicd_reg - GICD_ICPENDR); return 0; case GICD_ISACTIVER ... GICD_ISACTIVERN: @@ -457,14 +459,16 @@ static int vgic_v2_distr_mmio_write(struct vcpu *v, mmio_info_t *info) case GICD_CPENDSGIR ... GICD_CPENDSGIRN: if ( dabt.size != DABT_BYTE && dabt.size != DABT_WORD ) goto bad_width; - printk("vGICD: unhandled %s write %#"PRIregister" to ICPENDSGIR%d\n", - dabt.size ? "word" : "byte", *r, gicd_reg - GICD_CPENDSGIR); + printk(XENLOG_G_ERR + "%pv: vGICD: unhandled %s write %#"PRIregister" to ICPENDSGIR%d\n", + v, dabt.size ? "word" : "byte", *r, gicd_reg - GICD_CPENDSGIR); return 0; case GICD_SPENDSGIR ... GICD_SPENDSGIRN: if ( dabt.size != DABT_BYTE && dabt.size != DABT_WORD ) goto bad_width; - printk("vGICD: unhandled %s write %#"PRIregister" to ISPENDSGIR%d\n", - dabt.size ? "word" : "byte", *r, gicd_reg - GICD_SPENDSGIR); + printk(XENLOG_G_ERR + "%pv: vGICD: unhandled %s write %#"PRIregister" to ISPENDSGIR%d\n", + v, dabt.size ? "word" : "byte", *r, gicd_reg - GICD_SPENDSGIR); return 0; /* Implementation defined -- write ignored */ @@ -489,14 +493,16 @@ static int vgic_v2_distr_mmio_write(struct vcpu *v, mmio_info_t *info) goto write_ignore; default: - printk("vGICD: unhandled write r%d=%"PRIregister" offset %#08x\n", - dabt.reg, *r, gicd_reg); + printk(XENLOG_G_ERR + "%pv: vGICD: unhandled write r%d=%"PRIregister" offset %#08x\n", + v, dabt.reg, *r, gicd_reg); return 0; } bad_width: - printk("vGICD: bad write width %d r%d=%"PRIregister" offset %#08x\n", - dabt.size, dabt.reg, *r, gicd_reg); + printk(XENLOG_G_ERR + "%pv: vGICD: bad write width %d r%d=%"PRIregister" offset %#08x\n", + v, dabt.size, dabt.reg, *r, gicd_reg); domain_crash_synchronous(); return 0; -- 2.1.4